This invention relates to radio communications. More particularly, this invention relates to improving radio communications between two or more locations using handie talkies by incorporating in the use of a command post radio.
Handie talkies (HT) are handheld, portable two-way radio transceivers that allow communications between two parties. Handie talkies typically send signals over a very high frequency (VHF) band or an ultra high frequency (UHF) band. A VHF band ranges from about 136 MegaHertz (MHz) to about 174 MHz. A UHF band ranges from about 403 MHz to about 512 MHz. Repeaters are commonly used with handie talkies to extend the radio signals from one handie talkie to another. Handie talkies are often used, for example, by public safety departments including the police departments, fire departments, and emergency medical services (EMS).
As an illustration, firefighters commonly use a Battalion Car Cross Band Repeater system to communicate with one another using handie talkies. The Battalion Car Cross Band Repeater may include, for example, the following: a UHF handie talkie, a UHF mobile radio, a Cross Band repeater, and a VHF handie talkie. When there is a fire in a building, a firefighter from the fire floor will use a handie talkie to communicate with a first-due Battalion Chief who may be situated in the lobby of the building. The handie talkie is typically a 1-5 watt UHF handie talkie that generates a UHF signal on a particular channel (e.g., on channel 2 at a frequency of 485.1875 MHZ, or on another high-rise channel). The UHF signal is transmitted to the UHF mobile radio located outside of the building, for example, in a vehicle such as a Battalion car. The UHF mobile radio then sends the UHF signal to the Cross Band repeater also located in the Battalion car. The Cross Band repeater regenerates the UHF signal to a VHF signal (e.g., at a frequency of 153.83 MHz) at 5 watts to the VHF handie talkie held by the Battalion Chief.
The Battalion Chief can respond to the firefighter on the fire floor by using the VHF handie talkie to send a 5-watt VHF signal (e.g., 153.83 MHz) to the Cross Band repeater. The Cross Band repeater sends the VHF signal to the UHF mobile radio where the signal is regenerated to a UHF signal (e.g., 485.1875 MHz) at 40 watts to the UHF handie talkie on the fire floor.
The operation of the Cross Band Repeater system is dual simplex. Simplex communications occur when the radios transmit and receive signals over the same frequency. Duplex communications occur when the radios transmit on one frequency and receive on a different frequency via an infrastructure such as a building repeater. Duplex communications are often used with a building repeater for both security and maintenance crews. A drawback to this type of communication in the fire service is that the service must then depend on an infrastructure that is not controlled by the fire department. In some situations, the effectiveness of the building repeater can be compromised by fire, interruptions in power, or some other event. When such an event occurs, firefighters using the handie talkies may be prevented from communicating with one another.
There are several problems and limitations with the current Cross Band Repeater system. For the UHF handie talkie on the fire floor to effectively receive and transmit signals to the UHF mobile radio in the vehicle, the UHF handie talkie often needs to be near a window. Currently most high-rise ground communications originate from the core or elevator lobby on the fire floor or floor below. This makes the UHF handie talkies, which are currently 5 watts in strength, sometimes too weak to reach the Cross Band repeater in the vehicle.
In view of the foregoing, it would be desirable to provide more reliable radio communications between two or more locations using handie talkies by incorporating in the use of a command post radio.